The lack of food security leads us to turn to the riches of the forest, namely non-timber forest products (NTFP) and timber forest products (TFP). In Burkina, these products are a source of income for families, improv...The lack of food security leads us to turn to the riches of the forest, namely non-timber forest products (NTFP) and timber forest products (TFP). In Burkina, these products are a source of income for families, improving their living conditions. Tamarindus indica L. that is a NFTP, is widely used in both rural and urban areas. Unfortunately, tamarind is subject to attack by Caryedon serratus. Its biological activity begins on the fruit before the harvest. The aim of our study is to evaluate some biodemographic parameters of the insect pest C. serratus Olivier. First100 healthy T. indica pods were placed in contact with ten pairs of C. serratus for 24 hours. 25 pods, each carrying a maximum of two eggs, were divided into five batches of 5 pods. Then a pair of C. serratus aged less than 24 h was placed in contact with 4 healthy pods for 24 h. Every day, the pair was removed and transferred to another box containing 4 new healthy pods. A total of 20 replicates were performed. The results showed that C. serratus has an average lifespan of 14 days. However, the female (16 days) lived longer and laid an average of 34 eggs during her lifetime. The egg-laying period lasted 14 days, the number of eggs increased until reaching a maximum peak on the 4<sup>th</sup> day. C. serratus has an embryonic development time of 3 days and an emergence rate of 66.63%. However, the weight of males and females differed significantly (p = 0.0108). We found an intrinsic rate of natural increase of 0.12 and a population doubling time was 5.68 days. These results have enabled us to gain a better understanding of its development cycle and its capacity for regeneration. This allows us to implement control strategies for better stock protection.展开更多
A traditional process used by farmers in Chad consists in soaking slices of taro (Colocasia esculenta L. SCHOTT) in tamarind infusion, or in corn solution or in water over a 24-hour period to reduce the acridity of ta...A traditional process used by farmers in Chad consists in soaking slices of taro (Colocasia esculenta L. SCHOTT) in tamarind infusion, or in corn solution or in water over a 24-hour period to reduce the acridity of taro and facilitate cooking. The aim of this study was to assess the effect of traditional soaking on the in vitro digestibility of taro flour using or not using an α-amylase enzyme. The digestion without the enzyme has shown that the soaking processes improve the digestibility of taro flour (from 39.30% for the control sample to 75.11% (after tamarind infusion) and 78.67% (treatment with water) after 24 hours of soaking). Soaking over a 6-hour period and preferentially in tamarind infusion or in corn solution obtains highly digestible flour (around 95% of digestibility rate after 3 hours of enzymatic digestion).展开更多
Aims Addressing plant responses to water stress is critical to understand the structure of plant communities in water-limited environments and to forecast their resilience to future changes in climate.In a semiarid ag...Aims Addressing plant responses to water stress is critical to understand the structure of plant communities in water-limited environments and to forecast their resilience to future changes in climate.In a semiarid agroforestry system in the Sahelian savannah of Leona(Senegal),we selected nine common tree species and explored their stress-resistance mechanisms.These species represent a variety of life forms and are of high regional socio-economic importance.We hypothesized that different species would show different suites of traits to cope with water stress and expected to identify functional groups differing in strategies to withstand water shortage.Methods Along a dry and a wet season,we monitored four traits reflecting above-and below-ground strategies of resource acquisition such as predawn leaf water potential(ψpd),specific leaf area(SLA),leaf thickness and leaf area index(LAI).We also measured two mor-phological traits:trunk diameter and tree height.LAI andψpd were measured six times during the dry and rainy seasons,and the other traits were measured once.Important Findings We identified two functional classes subdivided into two func-tional groups of each class.The first class included deciduous and semi-deciduous species that generally had large SLA,low leaf thickness and small-to-intermediate inter-seasonal varia-tions inψpd.The second class included evergreen species of two functional groups that differ in SLA,leaf thickness and the mag-nitude of inter-seasonal variations ofψpd throughout the year.The four functional groups identified in this study represent plant strategies differing in their response to changing environmental conditions.展开更多
文摘The lack of food security leads us to turn to the riches of the forest, namely non-timber forest products (NTFP) and timber forest products (TFP). In Burkina, these products are a source of income for families, improving their living conditions. Tamarindus indica L. that is a NFTP, is widely used in both rural and urban areas. Unfortunately, tamarind is subject to attack by Caryedon serratus. Its biological activity begins on the fruit before the harvest. The aim of our study is to evaluate some biodemographic parameters of the insect pest C. serratus Olivier. First100 healthy T. indica pods were placed in contact with ten pairs of C. serratus for 24 hours. 25 pods, each carrying a maximum of two eggs, were divided into five batches of 5 pods. Then a pair of C. serratus aged less than 24 h was placed in contact with 4 healthy pods for 24 h. Every day, the pair was removed and transferred to another box containing 4 new healthy pods. A total of 20 replicates were performed. The results showed that C. serratus has an average lifespan of 14 days. However, the female (16 days) lived longer and laid an average of 34 eggs during her lifetime. The egg-laying period lasted 14 days, the number of eggs increased until reaching a maximum peak on the 4<sup>th</sup> day. C. serratus has an embryonic development time of 3 days and an emergence rate of 66.63%. However, the weight of males and females differed significantly (p = 0.0108). We found an intrinsic rate of natural increase of 0.12 and a population doubling time was 5.68 days. These results have enabled us to gain a better understanding of its development cycle and its capacity for regeneration. This allows us to implement control strategies for better stock protection.
基金grateful to Chad French Ambassy for the financing of this project.
文摘A traditional process used by farmers in Chad consists in soaking slices of taro (Colocasia esculenta L. SCHOTT) in tamarind infusion, or in corn solution or in water over a 24-hour period to reduce the acridity of taro and facilitate cooking. The aim of this study was to assess the effect of traditional soaking on the in vitro digestibility of taro flour using or not using an α-amylase enzyme. The digestion without the enzyme has shown that the soaking processes improve the digestibility of taro flour (from 39.30% for the control sample to 75.11% (after tamarind infusion) and 78.67% (treatment with water) after 24 hours of soaking). Soaking over a 6-hour period and preferentially in tamarind infusion or in corn solution obtains highly digestible flour (around 95% of digestibility rate after 3 hours of enzymatic digestion).
基金This work was carried out within the FUNCITREE Project,an EU 7FP(contract KBBE-227265)It was also partly funded by the Spanish MICINN(grant CGL2014-59010-R)J.S.D.received a PhD fellowship from the Spanish Agency of International Cooperation for Development(AECID).C.A.is grateful to the Spanish Government for her‘Ramón y Cajal’contract(RYC-2012-12277).
文摘Aims Addressing plant responses to water stress is critical to understand the structure of plant communities in water-limited environments and to forecast their resilience to future changes in climate.In a semiarid agroforestry system in the Sahelian savannah of Leona(Senegal),we selected nine common tree species and explored their stress-resistance mechanisms.These species represent a variety of life forms and are of high regional socio-economic importance.We hypothesized that different species would show different suites of traits to cope with water stress and expected to identify functional groups differing in strategies to withstand water shortage.Methods Along a dry and a wet season,we monitored four traits reflecting above-and below-ground strategies of resource acquisition such as predawn leaf water potential(ψpd),specific leaf area(SLA),leaf thickness and leaf area index(LAI).We also measured two mor-phological traits:trunk diameter and tree height.LAI andψpd were measured six times during the dry and rainy seasons,and the other traits were measured once.Important Findings We identified two functional classes subdivided into two func-tional groups of each class.The first class included deciduous and semi-deciduous species that generally had large SLA,low leaf thickness and small-to-intermediate inter-seasonal varia-tions inψpd.The second class included evergreen species of two functional groups that differ in SLA,leaf thickness and the mag-nitude of inter-seasonal variations ofψpd throughout the year.The four functional groups identified in this study represent plant strategies differing in their response to changing environmental conditions.